A volunteer is injected with an African-produced HIV vaccine during trials in Crossroads, Cape Town. Photograph: Rodger Bosch/AFP/Getty Images

There have been unprecedented developments in HIV vaccine research recently, but the field is threatened by the global downturn in funding for HIV/Aids. Ahead of the Aids Vaccine 2010 conference starting in Atlanta on 28 September, IRIN/PlusNews spoke to Mitchell Warren, executive director of the Aids Vaccine Advocacy Coalition, about the future of HIV vaccine research and development

Question: How much progress has been made?

Answer: Tremendous progress. Over the past year, scientists have identified neutralising antibodies against HIV, which are a fundamental building block for developing a vaccine. In addition, we had the Thai vaccine trial that for the first time ever showed we could have vaccine protection against HIV in humans. These are both game-changing developments.

The challenge is that we don't know how much further we need to go before we find a viable candidate. It's [as if] we are on a long journey and have come very far, but are not certain of the distance to the finish line. What we need is to better understand the steps along the way. We now know that large clinical trials are the best way to learn about the vaccine so we need to generate more ideas to improve the effectiveness of these trials and we definitely need to generate more of these trials.

Question: What are the biggest hurdles to developing a vaccine?

Answer: Science, science and science. There are still so many unknowns about the human immune system and how it works, and about the virus and its mutations and sub-types.

Funding is another big challenge. There is a need for long-term sustainable funding; more money is essential, but it is important for the money to also be sustainable – vaccine research is not a one-shot deal.

Question: With the downturn in HIV funding, where will the money come from?

Answer: The US has been funding more than 70% of vaccines research and development, and we hope that it will continue to fund the search for a vaccine. We also need to reach out to donors who have not supported vaccine research very heavily in the past – many of the G8 countries fall into this category.

Financing for HIV vaccine research went down by 10% two years ago and was flatlined last year.

It's easy to say we need more money, but everywhere there is a need for more money; what we need in HIV is to integrate with each other as much as possible. We have never had a better opportunity to translate new science into promising HIV vaccine candidates; at the same time, people around the world are lining up for scarce ARVs [antiretroviral drugs]. Investment must be strategic, because both these areas are hugely important.

Question: How much vaccine research is taking place in Africa by Africans?

Answer: Aids vaccine research is becoming increasingly globalised. In Africa, community after community and research team after research team are grasping hold of and owning the research process.

Of course, more collaboration is needed between the countries on the continent involved in research, but compared to 10 years ago, the face of HIV vaccine research has become increasingly international and increasingly African. The HIV vaccine will not be discovered in Washington DC or London, it will be found in Nairobi, in Entebbe, in Cape Town.

Question: The Thai RV 144 vaccine trial caused some controversy over the strength of the results. How significant were the findings?

Answer: This was a "proof of concept" study that sought to prove that the vaccine candidate could provide some protection against HIV in humans. It undoubtedly did so, and the collective scientific community believes the results of the Thai trial were real and exciting.

The challenge is really what to do with the results, how to move from "proof of concept" to a stage where a vaccine can have a public health impact. A good trial seeks to ask one question and answer it. A great trial answers the question and raises all sorts of new lines of inquiry. The Thai trial definitely did this, and there is now a healthy dialogue on how to proceed next.

Question: How ethical are today's vaccine trials?

Answer: Prevention trials are complex in nature – you are enrolling people at risk of HIV who are HIV-negative. But overall, today's trials are conducted incredibly well. UNAids and the World Health Organisation have come up with good guidance on conducting clinical trials.

It is important to know that prevention trials are essentially state-of-the-art prevention packages, with one arm of the trial receiving the comprehensive prevention package as well as the vaccine candidate, and another receiving the comprehensive prevention package and a placebo.

Informed consent is an integral part of HIV vaccine trials, as is counselling and support. Participants who happen to become infected with HIV must be given access to ARVs. Each ongoing trial has developed to provide care and treatment, not just to the trial participants but to the whole community.

It is getting easier to recruit trial participants because there has been a paradigm shift in the way trials are conducted. It is no longer a case of researchers coming into a community, conducting research and leaving. Now clinical trials are there for the long haul, getting to know and supporting the people they are working closely with, building trust. In many communities, these are not just trial sites, they are the places the community get their ARVs, their TB drugs – the trial is one part of a larger programme that supports the community in a variety of ways.

There is always more that can be done, but the bar is getting higher and higher and there are several groups that monitor trials to ensure they are sticking to ethical guidelines.

Question: Is there sufficient collaboration in HIV vaccine research?

Answer: It is becoming increasingly clear that no one can do this alone – no one country, research group, or clinical trial; it needs partnership. We need all the right disciplines involved, from basic scientists to researchers to labs and clinics in the developing world to industry partners.

There is definitely more data sharing and collaboration going on between the different players, which is very useful for improving research. Competition is also a good thing; it spurs researchers in the field to go further than their competition. The best scientific discoveries happen when people discuss things, challenge each other. We have to develop a community which understands the delicate balance needed between collaboration and competition.

If we do come up with a vaccine, collaboration with large companies will be crucial; we need to tap their technical expertise and tap it early so that we can ensure that any product is developed to ensure the people who need it the most – usually the poorest – have access to it.

It is important to work with the Global Alliance for Vaccines and Immunisation to build the political will and the market for the vaccines that these companies currently produce – that way, once a vaccine becomes available there is an incentive to produce it for a guaranteed, wide market.